A Compact Piezoelectric Tilt Table for Cryogenic Electron Microscopy

Abstract

This project designed, tested materials and machining techniques, and prototyped a piezoelectrically actuated motor to precisely orient a stage for a specimen within the compact space and restrictive environment of a transmission electron microscope (TEM). TEMs enable researchers to image and probe the structure of materials at the atomic scale, enabling advances in materials science, structural biology, and semiconductor scaling. However, many materials, such as superconductors, must be studied at cryogenic temperatures. Most materials and mechanisms that might be used to orient a specimen will not work at the very low temperatures, high vacuum, and magnetic fields within a TEM. Current specimen tilt stages typically use external DC motors which suffer from mechanical vibrations, instability, imprecision, and thermal drift affecting the specimen. There is a need to develop a tilting stage compact enough to fit within the TEM, precise enough to appropriately orient the specimen, and able to function within the cryogenic TEM environment.